:root {
  color-scheme: light dark;
  --bg: #f6f7f9;
  --card: #ffffff;
  --text: #1a1a1a;
  --muted: #5c6570;
  --link: #0b5fff;
  --border: #e5e7eb;
  --accent: #111827;
  font-family: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --card: #171a21;
    --text: #f3f4f6;
    --muted: #9ca3af;
    --link: #7eb6ff;
    --border: #2a2f3a;
    --accent: #f9fafb;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap {
  max-width: 760px;
  margin: 0 auto;
  padding: 32px 20px 64px;
}
header {
  margin-bottom: 28px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}
.brand {
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--muted);
  text-transform: uppercase;
}
h1 {
  margin: 8px 0 4px;
  font-size: 28px;
  line-height: 1.3;
  color: var(--accent);
}
.meta { color: var(--muted); font-size: 14px; }
nav.links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 12px;
  font-size: 14px;
}
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 24px 22px;
}
h2 {
  margin: 28px 0 10px;
  font-size: 18px;
}
h2:first-child { margin-top: 0; }
p, li { font-size: 15px; }
ul { padding-left: 1.2em; }
li { margin: 6px 0; }
.note {
  margin-top: 28px;
  padding: 14px 16px;
  border-radius: 10px;
  background: color-mix(in srgb, var(--link) 8%, transparent);
  color: var(--muted);
  font-size: 13px;
}
footer {
  margin-top: 28px;
  color: var(--muted);
  font-size: 13px;
}